On the morning of March 6 1995, teen lovers Ben Darras and Sarah Edmondson left their Oklahoma cabin and took the highway east. In Mississippi they came across a local businessman, Bill Savage, and shot him twice in the head with a .38-calibre revolver. They then swung across to Louisiana, where they gunned down convenience-store cashier Patsy Byers, paralysing her from the neck down. Darras and Edmondson were standard American brats who loved their hard drugs and their R-rated movies. After their arrest, it was revealed that they had prepared for the trip by dropping acid and screening Natural Born Killers on a continuous loop throughout the night.

No film in recent decades has stoked as much controversy as Natural Born Killers. No film-maker, if his critics are to be believed, has quite so much blood on his hands as its director, Oliver Stone. In the eight years since its release, Stone's picture has been confidently linked to at least eight murders - from Barras and Edmondson's wild ride, through the Texan kid who decapitated a classmate because he "wanted to be famous, like the natural born killers", to the pair of Paris students who killed three cops and a taxi driver and were later discovered to have the film's poster on their bedroom wall. The ensuing media storm ensured that the British Board of Film Classification sat on the film for six months before passing it for a theatrical release in February 1995. It also explains why we have had to wait until now for the release of Stone's director's cut on DVD.

Bankrolled by Time Warner, NBK dispatches psycho lovebirds Mickey (Woody Harrelson) and Mallory (Juliette Lewis) on a murderous, junk-culture joyride. Along the way it melds 35mm with Super-8, animation with back projection and stylised carnage with a thunderous rock soundtrack. The initial response was enthusiastic. The film sailed to the top of the US box office, with Variety dubbing it "the most hallucinatory and anarchic picture made at a major Hollywood studio in the last 20 years...a psychedelic documentary on the American cult of sex, violence and celebrity."

But as the body count mounted, the reaction turned icy. Mario Vargas Llosa publicly cursed the film at the 1994 Venice film festival. David Puttnam (who had previously worked with Stone on 1978's Midnight Express) labelled it "loathsome". In the opinion of the Daily Mail, NBK was simply "evil". "If ever a film deserved to be banned," it concluded, "this is it."

If the media were looking for a fall guy, they found him in Stone. To his critics, the director was a ready-made hypocrite: a rich kid who volunteered for Vietnam and then made Oscar-winning films (Platoon, Born on the Fourth of July) lambasting the war; a peace-loving Buddhist who freely admitted that movie violence was "cool". His film, too, was derided as hypocrisy in action: a supposed satire on screen violence that wallowed in two hours of stylised atrocity and then berated the viewer for getting off on it. Thus the director found himself cast as a wicked Svengali, with Natural Born Killers his murderous instruction manual.

Stone is not a man you would think of as a sensitive type. Eight years on, however, he admits that the flak left him shaken. "The controversy was huge, no question about it," he says now. "To my mind, almost everything that was important about Natural Born Killers was overlooked amid all that hysteria over the death toll, and all the nonsense about whether or not I was promoting violence or instigating murder."

Such "nonsense" came to a head in a legal action launched against Stone and Time Warner by lawyers acting for the paralysed Byers, and publicly supported by the author John Grisham, who had been a friend of the murdered Savage. According to the suit, the makers of Natural Born Killers were "distributing a film they knew, or should have known would cause and inspire people to commit crimes". Grisham agreed. There was, he said, a direct "causal link" between the movie and the murders. Therefore, "the artist should be required to share responsibility along with the nutcase who pulled the trigger".

The Byers action was finally thrown out of court in March 2001, and its dismissal rubber-stamped by the Louisiana court of appeal in June of this year. Stone, who says that Time Warner lost "a lot of money" fighting the case, is mightily relieved. "Once you start judging movies as a product, you are truly living in hell. What are the implications for freedom of speech? You wouldn't have any film of stature being made ever again."

He compares the lawsuit to the infamous case of Dan White, the ex-cop who shot San Francisco politician Harvey Milk in 1978. "White used what was known as the Twinkie defence. He said that he had been eating too many Twinkies and that the high sugar content had prompted him to kill. And it worked! He got away with a lesser charge of voluntary manslaughter and served five years. But you can't blame the Twinkies in the same way that you can't scapegoat the movies. You can't blame the igniter. People can be ignited by anything. And yet this is something we're seeing more and more of in America today. It's a culture of liability lawsuits. The whole concept of individual responsibility has been broken up and passed around."

I wonder, though, where Stone stands on this thorny issue of liability. Does he feel any measure of artistic responsibility for the films he makes? "That's a very leading question. Because there is no partial responsibility. If you make a film that results in people getting killed, then you are guilty. Therefore I'm not accepting any responsibility."

Surely, though, he wouldn't dispute the idea that a film can influence its viewer. "Of course it can. Maybe it inspires you to change your love life, or to alter your wardrobe. But it's not a film's responsibility to tell you what the law is. And if you kill somebody, you've broken the law."

If NBK has an obvious ancestor, it is A Clockwork Orange. And yet when Stanley Kubrick's movie was linked to various copycat crimes in the early 70s, the director personally had it whipped out of circulation. "Yeah, but I think Kubrick was wrong to do that," Stone argues. "If it wasn't an admission of guilt, it was at least an admission of embarrassment. I'm a big fan of Kubrick, but he was a paranoid man. He reacted to the hysteria of the mob. He crumbled when he should have stood up and defended his work."

Not that Stone didn't suffer some qualms of his own. "When people are attacking you, you are naturally going to have some doubts. 'Why I am making films? Why has this movie been so misunderstood?' And yes, people may have been influenced by the film in some way, but they had deeper problems to contend with. So I felt terrible about it all. In the end I went and hid myself away in a darkened room for a few years." Really? Reading interviews at the time, he struck me as being positively bullish in his defence. The director chuckles. "OK," he says. "Maybe I was joking about the darkened room."

Before permitting the release of NBK in 1994, the censors insisted that Stone strip a whopping 150 shots from the film. The new version restores them all, from a loving camera zoom through a bullet-holed hand to a climactic shot of Tommy Lee Jones's severed head on a stick. The director concedes that on one level this makes the director's cut a more obviously violent film. But he stresses that the restored segments are so over the top that they emphasise his satirical intent.

In other respects, the director's cut plays much like the original: an exuberant shotgun wedding of the crass with the sophisticated that closes with an extended channel-surf through the hot media imagery of the day (OJ Simpson, the Menendez brothers, the Waco siege). Viewed from our lofty 21st-century vantage point, it already seems something of a timepiece: a snapshot of a specific era in US culture; a tenuous accessory to crimes that have been duly tried, sentenced and consigned to history.

"Natural Born Killers was never intended as a criticism of violence," Stone explains. "How can you criticise violence? Violence is in us - it's a natural state of man. What I was doing was pointing the finger at the system that feeds off thatviolence, and at the media that package it for mass consumption. The film came out of a time when that seemed to have reached an unprecedented level. It seemed to me that America was getting crazier."

Since then, he has revised his opinion: "Oh, it's worse than ever now. The reaction of our culture to violence is more extreme than it's ever been. Just look at the events of September 11. I think that the media overreacted to it. Just like they overreacted to my little film."